In order to open and close the contact system of a vacuum interrupter, a moving contact moves along a central axis of the vacuum interrupter relative to a fixed contact. A switch drive provides a corresponding drive movement. A drive rod, which is of electrically insulating design and connects the switch drive to the vacuum interrupter, serves to introduce the drive movement into the moving contact connection bolt of the vacuum interrupter. Misaligned positions of this drive rod can occur both during assembly of the switch pole of the circuit breaker and also during operation of the circuit breaker.
The prior art discloses designing the stationary and/or the movable contact piece such that adequate functioning of the contact arrangement is ensured even when the drive rod is misaligned. This solution is expensive since particularly large contact areas are required.
The prior art likewise discloses using guide systems in order to preclude malfunctions of the switch pole from the outset for the purpose of avoiding incorrect orientations of the kind. Additional components and structural elements which are fitted to the pole shell, such as special guide bearings for example, are used for this purpose, as a result of which the structural design of the switch pole becomes comparatively complex.